While not limited thereto, the present invention is particularly directed to on-off valves used to dispense the contents of compressed gas cylinders. Such valves are subjected to high pressure and must be completely leak proof. Usually substantial manual force must be applied to open or close the valve, such that at filling plants operators use gloves. Most valves for this purpose are die casts and possibly have sharp edges. This coupled with the need for high manual force can injur the user's hand. Also, during the use of the pressure cylinder, there is a substantial pressure drop across the valve, often resulting in cooling the hand wheel below the freezing point of water, thus rendering the valve dangerous to grasp, particularly if a strong grip is required. Many times wrenches or other leverage devices are used which can cause damage to the valve and is considered unsafe.